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Paratransit Optimization with Constraint Programming: A Case Study in Savannah, Georgia

Authors Liam Jagrowski , Kevin Dalmeijer , Tinghan Ye , Pascal Van Hentenryck

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LIPIcs.CP.2026.31.pdf
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Subject Classification

ACM Subject Classification
  • Applied computing → Transportation
  • Theory of computation → Constraint and logic programming
  • Mathematics of computing → Combinatorial optimization
Keywords
  • Paratransit
  • Mobility as a Service
  • Constraint Programming
  • Case Study

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Abstract

Paratransit services are vital for individuals who cannot use fixed-route public transit, including those with disabilities. Optimizing these services is essential for transit agencies to deliver high-quality service efficiently. This paper introduces a Constraint Programming (CP) model to jointly optimize route planning and shift scheduling for paratransit operations, along with practical guidance for real-world implementation. A case study in Savannah, Georgia, demonstrates that the new approach is competitive with a recently proposed, highly effective AI-accelerated column generation framework, and significantly increases the number of requests served compared to current practices. The method is also easier to implement and provides an inherently practical solution for transportation planners. CP further provides the flexibility to optimize schedules without requiring shifts to start exactly on the hour, yielding an additional 5% improvement in the number of requests served.

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Liam Jagrowski, Kevin Dalmeijer, Tinghan Ye, and Pascal Van Hentenryck. Paratransit Optimization with Constraint Programming: A Case Study in Savannah, Georgia. In 32nd International Conference on Principles and Practice of Constraint Programming (CP 2026). Leibniz International Proceedings in Informatics (LIPIcs), Volume 379, pp. 31:1-31:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2026) https://doi.org/10.4230/LIPIcs.CP.2026.31

Author Details

Liam Jagrowski
  • H. Milton Stewart School of Industrial and Systems Engineering, Georgia Tech, Atlanta, GA, USA
Kevin Dalmeijer
  • H. Milton Stewart School of Industrial and Systems Engineering, Georgia Tech, Atlanta, GA, USA
Tinghan Ye
  • H. Milton Stewart School of Industrial and Systems Engineering, Georgia Tech, Atlanta, GA, USA
Pascal Van Hentenryck
  • H. Milton Stewart School of Industrial and Systems Engineering, Georgia Tech, Atlanta, GA, USA

Funding

This research is partly supported by NSF awards 2112533 and 1854684.

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